Conventional projectiles, such as bombs or missiles, have movable fins which help to steer the projectiles toward a particular target. In certain situations, such as prior to launch or during transportation, a locking mechanism holds the fins in a zero angle of attack position relative to the projectile's centerline. Such locking minimizes wear, overstressing, and the possibility of damage to the fins and associated steering systems. Additionally, the locking mechanism allows for release of the fins at the time of use so that the fins can be driven to computer controlled positions.
Conventional locking mechanisms can be transitioned from a locked state to an unlocked state in a variety of ways. For example, the locking mechanism can be configured as an explosive release mechanism having an explosive squib. The explosive squib can include a small tube that contains an explosive substance and a detonator disposed along a length of the tube. Initially, the explosive squib holds a release mechanism against the fins of the guided munitions to maintain the fins in an aligned or non-deployed position. When the detonator receives an electric discharge signal, the detonator detonates the explosive squib to release the lock mechanism. With such a release, the lock mechanism allows the fins to move from the non-deployed or locked position to a deployed position. Other conventional locking mechanisms include brakes, solenoids, and fin lock release motors configured to hold the fins in a retracted or stationary state and release the fins to allow the fins to move to a deployed position.
In addition to the locking mechanism, conventional projectiles can also include a driving mechanism to adjust the position of the fins during operation. For example, certain projectiles include a Control Actuation System (CAS) having an actuator, such as a motor, and an electronic controller, such as a flight computer. In use, the actuator is configured to adjust the position of the fins in response to steering commands received from the controller to steer the projectile along a flight path toward a target.